ESV Study Note on John 4:18

John 4:18 The woman had had five husbands who had either died or divorced her. When Jesus says the one you now have is not your husband, he implies that merely living together does not constitute a marriage. A marriage requires some kind of official sanction and public ceremony at which a man and woman commit to the obligations of marriage and the community then recognizes that a marriage has begun (see 2:1; also Song 3:11; Mal. 2:14; Matt. 9:15). Sexual relationships prior to marriage were without question thought to be morally wrong (Gen. 38:24; Ex. 22:16; Deut. 22:13–29;Matt. 15:19; John 8:41; Acts 15:20; 1 Cor. 6:18; 7:2, 9; 1 Thess. 4:3; cf. the imagery in 2 Cor. 11:2).

Question: "What does the Bible say about sex before marriage?"

Answer: There is no Hebrew or Greek word used in the Bible that precisely refers to sex before marriage. The Bible undeniably condemns adultery and sexual immorality, but is sex before marriage considered sexually immoral? According to 1 Corinthians 7:2, "yes" is the clear answer: "But since there is so much immorality, each man should have his own wife, and each woman her own husband." In this verse, Paul states that marriage is the "cure" for sexual immorality. First Corinthians 7:2 is essentially saying that, because people cannot control themselves and so many are having immoral sex outside of marriage, people should get married. Then they can fulfill their passions in a moral way.  (Rich adds, verse 9 says the same thing)

Since 1 Corinthians 7:2 clearly includes sex before marriage in the definition of sexual immorality, all of the Bible verses that condemn sexual immorality as being sinful also condemn sex before marriage as sinful. Sex before marriage is included in the biblical definition of sexual immorality. There are numerous Scriptures that declare sex before marriage to be a sin (Acts 15:20; 1 Corinthians 5:1; 6:13, 18; 10:8; 2 Corinthians 12:21; Galatians 5:19; Ephesians 5:3; Colossians 3:5; 1 Thessalonians 4:3; Jude 7). The Bible promotes complete abstinence before marriage. Sex between a husband and his wife is the only form of sexual relations of which God approves (Hebrews 13:4).

Far too often we focus on the "recreation" aspect of sex without recognizing that there is another aspect—procreation. Sex within marriage is pleasurable, and God designed it that way. God wants men and women to enjoy sexual activity within the confines of marriage. Song of Solomon and several other Bible passages (such as Proverbs 5:19) clearly describe the pleasure of sex. However, the couple must understand that God's intent for sex includes producing children. Thus, for a couple to engage in sex before marriage is doubly wrong—they are enjoying pleasures not intended for them, and they are taking a chance of creating a human life outside of the family structure God intended for every child.

While practicality does not determine right from wrong, if the Bible's message on sex before marriage were obeyed, there would be far fewer sexually transmitted diseases, far fewer abortions, far fewer unwed mothers and unwanted pregnancies, and far fewer children growing up without both parents in their lives. Abstinence is God's only policy when it comes to sex before marriage. Abstinence saves lives, protects babies, gives sexual relations the proper value, and, most importantly, honors God.  From http://www.gotquestions.org/sex-before-marriage.html  

Carefully Review These Verses - Where do those who indulge in sexual sin go when they die?

Woman at the well  John 4.18 "for you have had five husbands, and you aren’t even married to the man you’re living with now. "   

• John MacArthur note on this verse "She was living conjugally with a man who Jesus said was not her husband.  By such an explicit statement, our Lord rejected the notion that when two people live together it constitutes marriage.  Biblically, marriage is always restricted to a public, formal, official, and recognized covenant.

1 Corinthians 7.2-3  But because there is so much sexual immorality, each man should have his own wife, and each woman should have her own husband.  3 The husband should fulfill his wife's sexual needs, and the wife should fulfill her husband's needs.

1 Corinthians 7.8-9  So I say to those who aren't married and to widows—it's better to stay unmarried, just as I am. 9 But if they can't control themselves, they should go ahead and marry. It's better to marry than to burn with lust.

1 Corinthians 5:11  I meant that you are not to associate with anyone who claims to be a believer yet indulges in sexual sin, or is greedy, or worships idols, or is abusive, or is a drunkard, or cheats people. Don’t even eat with such people. 12 It isn’t my responsibility to judge outsiders, but it certainly is your responsibility to judge those inside the church who are sinning. 13 God will judge those on the outside; but as the Scriptures say, “You must remove the evil person from among you.

1 Corinthians 6:9-10  Don’t you realize that those who do wrong will not inherit the Kingdom of God? Don’t fool yourselves. Those who indulge in sexual sin, or who worship idols, or commit adultery, or are male prostitutes, or practice homosexuality, 10 or are thieves, or greedy people, or drunkards, or are abusive, or cheat people—none of these will inherit the Kingdom of God. 

1 Corinthians 6.18  Run from sexual sin! No other sin so clearly affects the body as this one does. For sexual immorality is a sin against your own body.

1 Corinthians 10.8  And we must not engage in sexual immorality as some of them did, causing 23,000 of them to die in one day.

Galatians 5.19-21  When you follow the desires of your sinful nature, the results are very clear: sexual immorality, impurity, lustful pleasures, 20 idolatry, sorcery, hostility, quarreling, jealousy, outbursts of anger, selfish ambition, dissension, division, 21 envy, drunkenness, wild parties, and other sins like these. Let me tell you again, as I have before, that anyone living that sort of life will not inherit the Kingdom of God.

Ephesians 5.3-5  Let there be no sexual immorality, impurity, or greed among you. Such sins have no place among God's people. 4 Obscene stories, foolish talk, and coarse jokes—these are not for you. Instead, let there be thankfulness to God. 5 You can be sure that no immoral, impure, or greedy person will inherit the Kingdom of Christ and of God.

Colossians 3.5-6  So put to death the sinful, earthly things lurking within you. Have nothing to do with sexual immorality, impurity, lust, and evil desires. Don't be greedy, for a greedy person is an idolater, worshiping the things of this world. 6 Because of these sins, the anger of God is coming.

1 Thessalonians 4.3-5  God's will is for you to be holy, so stay away from all sexual sin. 4 Then each of you will control his own body and live in holiness and honor—5 not in lustful passion like the pagans who do not know God and his ways.

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Why should I save sex for marriage?